This invention relates to a process for the production of hydroquinone by the hydrogenation of nitrobenzene to an amino product and the hydrolysis of the amino product to hydroquinone.
Hydroquinone is a widely used organic reducing agent. It has the characteristic of being easily oxidized to quinone and the quinone-like products. The principal large scale used of hydroquinone is as a photographic developer. Hydroquinone also inhibits the autoxidation of various materials and is used as an antioxidant for substances such as fats, oils, whole milk powders, vitamins, and the like.
Hydroquinone has been produced heretofore commercially by the oxidation of aniline in sulfuric acid with manganese dioxide or sodium dichromate to quinone and the reduction of the quinone with iron dust in water to hydroquinone. Other suggested methods of production have included the hydrolysis of p-halogenated phenols with aqueous alkali metal hydroxide solutions and the electrolytic oxidation of benzene to quinone in sulfuric acid and the later reduction of the quinone to hydroquinone. My copending application Ser. No. 267,534 describes the productioon of hydroquinone by the hydrolysis of para-aminophenol.